• President, Consortium of Independent Immunology Clinic in North America (CIIC). 2013 - 2016.
  • Associate Clinical Professor at The University of Texas Southwestern Medical Center at Dallas. 1992 - 2016.
  • Head of The Cellular Immunology Laboratory at The University of Texas Health Center at Tyler (UTHCT). 1986 - 1992.
  • Acting Chairman of The Pediatric Pulmonology Department at UTHCT. 1991 - 1992.
  • Associate Professor and Division Head of Allergy & Immunology and Research Associate Professor in Immunology at UTHCT. 1986 - 1992.